You very likely adore your kitty, but you almost certainly loathe the smell of her urine. And if she's ever peed where she shouldn't, then you know that the sour smell of cat urine is not only terrible but incredibly hard to get rid of. You can spray cleaners, scrub until your arm hurts and cover the spot with perfumes, but in a few days time, sure enough, that familiar, nauseating cat pee smell is right back where it was. But rest assured, you can remove the smell — if you treat the stain properly.
Remove the urine
If your cat has just peed, remove as much of the urine as possible before it dries. As Petfinder points out, the less pee that sinks in, the less you'll have to clean up later and worse, the longer it stays in place, the more it smells. Blot the spot with an absorbent paper towel, or if it's on something that can be picked up and thrown in the wash, like your sheets, throw it in the washing machine as soon as possible. Try to use laundry detergent with baking soda or an enzyme cleaner in it if you have one on hand, and if not, add up to one pound of baking soda to your usual amount of detergent.
Use an enzymatic cleaner
Tackle the smell with an enzymatic cleaner to break down the urine itself. Most cleaners don't do this, and without enzymes, you're just going to keep cleaning and cleaning without making much of an impact on the cat urine smell itself. Apartment Therapy recommends using BacOut or Nature's Miracle. If you want to make sure the smell disappears, you may also try a commercially available cat urine remover designed for that specific purpose. Whatever product you choose, always follow product directions and test it on a discreet corner of the surface you are cleaning first to make sure it does not stain or bleach the material.
Even if you think you can get rid of the smell with a traditional cleaner, remember that your cat has a much better sense of smell than you do, and if he can smell it, he will be more likely to urinate there again according to PetMD. So for that reason alone, always use an enzyme-based cleaner or something designed specifically for cat urine.
Cleaning cat urine from carpet
You'll want to be sure you pull any remaining urine from the flooring and also extract any chemicals left in the carpet at the same time, so use an extracting wet vac after first blotting out the liquid and then cleaning the stain with an enzymatic cleaner. Because enzyme cleaners don't always work well with other cleaners, you should stick with using just clean, cool water in the wet vac.
Whatever you do though, avoid using a steam cleaner because according to the Humane Society, these can cause odors to set into carpet fibers, making them more difficult to clean.
Paint or varnish damage
The chemicals in urine can eat away at paint and wood varnish. This won't usually happen overnight, so it's most likely to happen in a hidden area of your home you didn't immediately notice your cat was urinating in or next to her litter box. If you do notice paint or varnish has been damaged by urine, you will likely need to remove and replace the damaged paint or varnish.
On the upside, washable enamel paints and some washable wallpapers respond well to enzymatic cleaners, so these may be fine if your cat has peed on them and are also a good solution if you need to repaint your wall in an area your cat is likely to pee on again.
A note about baking soda
Baking soda is a great odor remover and can help get rid of cat urine smell, but it is dangerous for cats and dogs to eat in large quantities. That's why you should keep your pets away from any surface you apply baking soda to until you thoroughly vacuum or otherwise extract the baking soda.